Method for treating with tannin oleaginous and proteinic material of vegetable origin, and products obtained by said method

ABSTRACT

Treatment of oleaginous and proteinic vegetable substances by adding a tannin-containing substance thereto, submitting the vegetable substance to mechanical pressure and friction forces in the presence of water at a temperature higher than normal ambient temperature while adjusting the amount of water such that it corresponds to a moisture content of about 10-15 percent of the vegetable substance, and separating the oily constituents from the proteinic constituents.

United States Patent [72] Inventors Zelrnen Zelter Paris; JeanDelort-Laval, La Verriere; Jean Lassonnery, Saint Junien; JacquesRodeaud, Chabanais, all of France [21] AppLNo. 711,885 [22] Filed Mar.11, 1968 [45] Patented Jan. 4, 1972 [731 Assignees Institut National dela Recherche Agronomique Paris, Prodults Chlmlques et Celluloses ReyVellzy-Vlllacouhlny, Yvelines, France [32] Priority Mar. 10, 1967 [3 3]France 3 1 1 98223 [54] METHOD FOR TREATING WITl-I TANNIN OLEAGINOUS ANDPROTEINIC MATERIAL OF VEGETABLE ORIGIN, AND PRODUCTS 2,354,719 8/1944Verbeck 3,507,662 4/1970 Leroy et al 99/2 2,288,662 7/1942 Weigel260/4122 2,533,858 12/1950 Weigel 260/4122 2,618,643 11/1952 Dunning260/4122 3,437,488 4/1969 I-Iumphreys 99/3 FOREIGN PATENTS 1,453,2619/1966 France 1,461,364 11/1966 France OTHER REFERENCES AnimalFoodstuffs, Harry De Moor, Chemical Abstracts, Vol. 65, 1966, column20761.

Feeds Resulting From The Reaction Between Nitrogencontaining AndTannin-containing Substances," R. A. Cardenas, Chem. Absts., Vol. 67,1967, article 2286e.

Protection Of Dietary Proteins From Rumen Bacterial Deamination.Artificial Rumen Studies," Dv l-I. Cox, Chem. Absts., Vol.65, 1964,article 16557h.

C R. Acad. Aug. 24, 1964, pp. 1,592- 1,595.

Primary Examiner-Norman Yudkoff Assistant ExaminerCurtis P. RibandoAttorney-Holman & Stern ABSTRACT: Treatment of oleaginous and proteinicvegetable substances by adding a tannin-containing substance thereto,submitting the vegetable substance to mechanical pressure and frictionforces in the presence of water at a temperature higher than normalambient temperature while adjusting the amount of water such that itcorresponds to a moisture content of about 10-15 percent of thevegetable substance, and separating the oily constituents from theproteinic constituents.

METHOD FOR TREATING WITH TANNIN OLEAGINOUS AND PROTEINIC MATERIAL OFVEGETABLE ORIGIN, AND PRODUCTS OBTAINED BY SAID METHOD The presentinvention relates to vegetable, oleaginous, proteinic substances and,more particularly, to the industrial fields concerned with oils,vegetable fats, oil cakes and other products abstracted from fruit,seeds, and other oleaginous, proteinic vegetable substances.

The invention has for its object a method for improving the rawmaterials and products of the industrial treatment of oleaginous andproteinic vegetable substances, said method comprising the steps oftreating said substances with at least one tannin-containing substance,and then separating the oily and greasy substances contained in thetreated vegetable substances. The tannin-containing substances may bemixed with the vegetable substances and the resulting mixture submittedto mechanical pressure and friction stresses in the presence of water,at a temperature higher than the normal ambient temperature.

The treatment according to the invention may be carried out by using asolid powderous tannin-containing substance, or a concentrated solutionof a tannin-containing substance, and particularly by using natural orsynthetic tannin-containing extracts; tannin-containing raw vegetablesubstances may also be used.

The novel treatment may advantageously be carried out at a temperaturehigher than 50 C., the moisture contents of the mixture constituted bythe vegetable and the tannin-containing substances being comprisedbetween and percent.

For the treatment of vegetable substances, such as peanuts, sunflower,colza, cotton, soya, linseed, amounts of about 3 to percent of thetanning extract may be used.

In the treatment of seed such treatment is advantageously carried outafter peeling or decortication of the grains.

The tannin-containing substance may be added to oleaginous substancesduring the oil-making operations, particularly prior to the calenderingor pressing operations.

The method according to the invention allows for producing improvedvegetable oils and fats, and oil-free vegetable cakes having a highernutritive value due to the protection of the proteinic substancesagainst bacterial deamination in the rumen.

The invention has also for its object the oils, fats, cakes, and otherproducts extracted from oleaginous proteinic substances by means of themethod hereinabove, as well as fruit, seeds, and other vegetableoleaginous proteinic substances treated with a tannin-containingsubstance, in accordance with the above-mentioned method.

In accordance with known methods, oil cakes are treated withtannincontaining substances with a view to improving their nutritiveproperties by rendering the proteins insoluble and forming with thelatter complex substances which are inaccessible to the bacterialdeaminases, but which can be dissociated by the proteolytic enzymes ofthe digestive tract.

Such tannin treatment of the oil cakes involves no danger for the animalbut considerably improves the nutritive properties of the cake,especially where ruminants are concerned, as the latter are particularlysubject to bacterial deamination in the rumen.

The tannin-containing substance may be constituted by a raw tanningextract, or by a tanning extract in the form of a powder, a paste, asuspension, a dispersion, or a solution in any convenient solvent.

The amounts of tannin-containing substance to be used will varyaccording to the amount of tannin which they contain. The type oftannin-containing substance to be used will depend on the nature of theoleaginous seed to be treated and on the proneness of the proteins to bedeaminated. The said amounts must be sufiicient for renderingpractically insoluble the proteins and prevent the partial or totalconversion of the proteins into ammoniac by the action of themicro-organisms in the digestive tract of the animal.

For the treatment of peanut, sunflower and soya the maximum such amountis about 15 percent. For the treatment of colza, said amount is about 12percent, and for the treatment oflinseed, an amount of only 6 percentwill be used.

These amounts are optimum amounts from a technical point of view; theymay be reduced on the ground of economical considerations, however, suchdecrease will result in a decrease of the improvement of the treatedproduct.

The method according to the invention provides not only for improvementof the value of the proteins, but also for improvement of the conditionsof its extraction and of the properties of the extracted oils and fats.The tannin-containing substances may be used in the form of powders,pastes, suspensions or solutions; they may also be used in the form ofraw tannin substances, provided they contain a sufficient amount oftannin for protecting the protein of the seed and other oleaginousproteinic vegetable substances without altering the nutritive propertiesof the resulting products such as oil cakes and oils.

The tannin-containing substances may be added during the conventionaloil-making operations without any substantial modification of the usualmanufacturing conditions, such as crushing, peeling, calendering,dressing, solvent extraction, thermal treatment (toasting), debittering.

In a particularly advantageous embodiment of the instant method, thetannin-containing substance is added prior to the calendering and, whereapplicable, after peeling or decortication, with a view to preventinglosses of tannin-containing substance. The distribution of thetannin-containing substance in the oleaginous substance must behomogenous, and effective contact must be obtained between thetannin-containing substance and the proteinic substances. Calenderingand pressing, which are conventional operations in the oil-makingindustry, provide for effective contact between the tannin-containingsubstance and the protidic substance, as the considerable mechanicalaction exerted during these operations involve pressure and friction.Furthermore, the steam usually introduced during the pressing operationresults in an increase in moisture and temperature, which contributes toimprove the contact between the various constituents of the mixture, andincreases the reactivity and affinity between the tannin and theprotein.

The conventional operations carried out in the oil-making process, andwhich vary in accordance with the nature of the oleaginous material tobe treated and in accordance with the traditional working method of anyparticular plant, are sufficient to ensure the efficiency of the methodaccording to the invention, as evidenced by the tannintreatment of theproteins of oil-free oilcakes.

The following examples illustrate the present invention; however, theyare not to be construed as involving any limitation of the scope of thepresent invention as defined herein.

EXAMPLE 1 A bulk quantity of peanut grains is decorticated and dividedinto 2 parts. The first part which serves as reference material iscrushed into fragments of the size of a rice grain and then treated intothe conventional manner by calendering without adding any additionalsubstance, and then solvent extraction.

One hundred parts of peanut grains of the above-mentioned second part,containing 95 percent of dry matter and 35 percent of protidic oilcakeare crushed on serrated cylinders.

Eight parts of tanning extract of chestnut wood in the form of a finepowder are added in as homogenous a manner as possible. This can beeffected, for instance, by uniformly sprinkling on a conveyor belt, orby mixing in a mixer. The homogenous mixture is heated to C. and itsmoisture contents is brought to about 10-12 percent by steam injectionprior to forwarding said mixture to a flake-producing calendering andpressing station.

The tannin-treated material coming from the calendering and pressingstation is allowed to rest for about 12 hours so as to enhance theswelling of the proteins and the fixing of the tannin on theirmolecules. This material is then submitted to the usual operations ofextraction by means of a solvent (hexane, essence B, etc.), andelimination of volatile substances.

Furthermore, the oil is submitted to convenient conventional treatmentsuch as degumming, decoloration, filtration and the like.

EXAMPLE 2 In this modified embodiment the mixture of peanut and tanningextract is not treated by means of a flake-producing calendering andpressing device, but laminated by means of smooth cylinders, whichproduces chips having a diameter of 3 to 4 cm. and a thickness of about0.1 mm. These chips are shaped into bands while steam is injected so asto heat the material to about 70 to 80 C. and to bring its moisturecontents to about to 12 percent. The extraction process is then effectedas indicated in example l, using the above-mentioned bands.

EXAMPLE 3 In another modified embodiment the tanning extract is added byatomization of a hot concentrated solution in a horizontal mixer. Onaccount of the amount of water thus introduced in the material thesubsequent operation of mechanical treating and extraction are effectedin a dehydrating atmosphere so that the oleaginous substance reaches theextracting station with a convenient moisture contents.

TEST OF THE EFFICIENCY OF THE TREATMENT, USING ARTIFlClAL RUMENS Theoil-free oilcake obtained from the reference grains which have not beentreated with tannin and the oilcake treated in accordance with thepresent invention are introduced into artificial rumens and contactedfor 15 hours with the contents of the rumen of living sheep. in thismanner the phenomena of bacterial deamination of the proteins which takeplace in vivo in the rumen of the animal are reproduced approximately,in vitro.

It is observed that the proteins of the nontreated oilcake are renderedsoluble in an amount of 65 percent in the artificial rumen, while 61.2percent of their total nitrogen contents are converted into ammoniac.

As opposed hereto the proteins of the tannin-treated oilcake arerendered soluble only in an amount of 6.4 percent, while only 4.8percent of their total nitrogen contents is converted into ammoniac.

The complex proteins of the oilcake treated according to the inventionare entirely liberated by the proteolytic enzymes (pepsine trypsine) ofthe digestive tract. The quantity of total nitrogen digested in vitro bythese enzymes represents 98.9 percent of the proteins of thetannin-treated oilcake, as compared to the corresponding value of 98.3percent of the proteins of the nontreated oilcake.

The degradation of the cellulose of coarse fodder under the action ofthe micro-organisms in the rumen does not undergo any modification bythe tannin treatment of the seed in accordance with the invention. Thus,the cellulose of wheat straw introduced in the artificial rumen isdegradated in an amount of 3 l .9 percent in the presence oftannin-treated oilcake as compared to 32.8 percent in the presence ofnontreated oilcake. In the absence of any oilcake this degradation takesplace only in an amount of 26.7 percent. The properties of the oilcakeobtained by the method according to the invention are in conformity withthose of the tannin-treated oilcakes prepared by known methods,particularly by the methods described in the following publications:

Leroy F, Zelter S. 2., Francois A. C., 1964 Protection of the AlimentaryProteins against Bacterial Deamination in the Rumen." C. R. Acad. S.Paris, 259, 1,592-1 ,595.

Leroy F, Zelter S. Z., 1966 Tanning of Peanut and Soya Oilcake Proteinsand Deamination Phenomena in the Rumen of Adult Sheep." 9th intern.cong. of Animal Prod, Edinburgh p. 137.

Leroy F, Zelter S. Z., Francois A. C. 1966 Protection of the AlimentaryProteins against Bacterial Deamination in the Rumen." 7th intern. cong.of nutr., Hamburg, and the French Patent specification No. 1.453.261 and1.461.364.

During the extraction of oil from seeds treated in accordance with theinvention it is observed that the percolation is improved whichfacilitates the oil extraction by means of a solvent. Furthermore, thegums or mucilages exhibit better coagulation which allows for faster andmore complete filtering and thus for better degumming of the oil.

The iron, copper, and cobalt contents of the resulting oil is lower thanthat of the oil obtained from seed which has not been treated withtannin; this enhances the resistance of the oil to rancidity.

Furthermore, it has been observed that the oil obtained fromtannin-treated seed blackens less easily when exposed to heat, ascompared to oil obtained from nontreated seeds.

EXAMPLE 4 Semi-industrial tannin-treating tests were conducted withcakes obtained from peanut grains having the following composition (byweight):

Water 4 .5 5% Fatty matter (related to the dry matter) 50. [0% Acidity(expressed in terms of oleic acid) 0.58%

A tanning extract in the form of a concentrated aqueous solution wasadded in an amount of 8 parts (by weight) of dry tanning extract forparts (by weight) of grains.

The test have been conducted in accordance with the conventionaltechnique of the oil extracting industry. The successive treatmentphases are generally the following:

i. Crushing (or flattening) of the grains 2. Baking of the crushedgrains (for about half an hour at lO0-120 C. until the crushed grainsdisgorge the oil).

3. One or more pressing steps for obtaining a residual product whichstill contains 5 to 10 percent oil.

4. Reheating, if desired, with a view to drying the product to apredetermined moisture contents.

5. Solvent extraction, whereby a residual product containing about 1percent oil is obtained.

The various tests hereinbelow have been conducted on the basis of theabove-described technique.

TEST A This is a reference test. The treatment is effected on peanutgrains without addition of tannin.

TEST B The tannin was incorporated after the crushing of the gains priorto the baking, i.e., between phases (1 and (2); the treatment was thencontinued without any maturing time or other resting periods during anyof the subsequent treatment phases.

TEST C The tannin was incorporated as in the test B, i.e., betweenphases (1 and (2), however, after phase (3) i.e., upon leaving the pressthe product was rehumidified up to a moisture contents of 12 percent,and the humidified product was allowed to rest for 1 night (maturing)and then dried (phase (4)) to a moisture contents of about 3 percent;subsequent phase (5), i.e., the oil extraction was then carried out.

TEST D The tannin was incorporated as in test B and C hereinabove, i.e.,prior to feeding the material into the baking device (phase (2)),however, the product was rehumidified after phase (2),

i.e., upon leaving the baking device, so as to have a moisture contentsof 12 percent; the product was then allowed to rest (maturing) for 4hours prior to phase (3), whereafter phases (3), (4), (5) were carriedout in an uninterrupted fashion.

TEST E In this test the tannin was incorporated immediately prior tophase (5). In this case, phase (4) needs not to be carried out, thetanning extract solution being introduced in the oleaginous productwhich has just undergone the last operation of the pressing phase (3).Extraction phase (5) was then carried out.

In test E series the pressing phase (3) was effected by two successivesteps: A first pressing step and a second and final pressing step, whichis a well-known technique in the oil-making industry.

In test C the extraction was carried out successively on two batches ofbags coming from the previous treatment phases. The correspondingproducts will be designated B1 and C1, respectively.

In a general way no particular difficulty in the extraction of the oilof the tannin-treated grains was encountered during the above tests.Furthermore, the tannin treatment by causing the flakes to hardenprevents the formation of dust, and the clogging of the filters, whichresults in a decrease of extraction time. Thus, the utilization of atanning extract improves the technology of extraction.

Hereinbelow indications will be given about the properties of the peanutcakes which were treated in the above tests, and he properties of theoils which were obtained.

1 Properties of Oil-free and Tannin-treated Peanut Cakes l l. Tests inthe Artificial Rumen In the artificial rumen the ammoniacal nitrogencontents (NNH3) as found with respect to the total nitrogen contents ofthe cake. The results are indicated in table I hereinbelow:

percent 0 Table I shows clearly a decrease of the ammoniogenesis for allthe preparations where the tannin was incorporated prior to the bakingoperation. Test E shows results less satisfactory for the industrialpractice although the relative decrease with respect to the nontreatedcake is still quite considerable.

l-2. Tests In Vivo Nutrition tests in vivo were conducted on malecastrated fistulated lle de France sheep. The evolution of the solubleand insoluble nitrogenous complexes was examined in the rumen of thesheet after a meal comprising percent of tannin-treated oilcake whichrepresented about 80 percent of the total nitrogen of the food ration.

Table I1 hereinbelow indicates the results.

The tests were conducted with cakes treated in conformity with tests Band C, the reference cake being the cake resulting from test A.

Table II Digestion time 'N.nP= concentration in milligrams of nonproteicnitrogen (i.e., ammoniucal N soluble nonammoniacal N) for I00milliliters of rumen liquid.

"N-NHI! concentration in milligrams of ummoniacal nitrogen for I00 milliliters of rumen liquid.

"N.nP.NH3 concentration in milligrams of nonummoniacul nonproteicnitrogen for I00 milliliters of Rumen liquid.

In table II the value has been assigned to the results obtained at zerotime for each material. The indicated values concerning cakes B and Care relative values related to the base 100 of the reference material.

2. Properties of the Resulting Oils Four oils prepared during the abovetests (A, B, C and E) are refined by a conventional method comprisingthe successive treatment steps of:

degumming and neutralization decoloration deodorization The followingobservations are recorded:

2l: During the degumming (demucilaginating) and neutralizing operationthe most favorable percentage of the total losses was obtained for theoil resulting from test B. However, the neutralization carrying offcoefficients (i.e., the percent ratios of the total losses at theacidity degree of the oil) are the following in the order of decreasingquality:

Oil A 5.5l Oil 8 5.60 Oil C 2.88

Oil D 5.00

Thus oil C shows the best refining coefficient. In all phases the oilswhich has been treated with a tanning extract gave the best results.

22: When comparing the four raw oils (mixture of pressure oil andextraction oil) it is seen that the tannin-treated oils have a lowerphosphor contents and thus a lower contents of gums than that of thereference oil. This property may be advantageously used in the treatmentof oils having a higher contents of phosphor lipid than that of thepeanut oil, such as colza oil, linseed oil, and soya oil.

23: The tannin-treated oils exhibit better properties as far as acidityand ultraviolet absorption are concerned. The following results wereobtained with ultraviolet rays:

at 232 mp.(dienic oxidation compounds) Oil A 2.88 Oil 8 2.46 Oil C 2.46Oil D 2.64

at 270 mmtrienic oxidation compounds) Oil A 4.50 Oil 8 4.38

Oil C 3.84 Oil D 3.60

These tests which were conducted on deodorized oil show that the tannintreatment improves the resistance of the oils to oxidation. 24: Theorganoleptic data have been recorded after conservation for a period of55 days. The samples were examined at that time by a testingjury whoarrived at the following classification:

The difference observed by the jury between oil D, C and B was hardlynoticeable, but the reference oil A was clearly put aside and its tastewas considered less pleasant.

it follows from these tests that the tannin treatment of peanut does notresult in a modification of the indices of oil obtained by pressing andextraction, while the refining conditions are favorably influenced bythe addition of tannin, the latter improving furthermore the conditionsof conservation of the oil, all other data being equal.

While certain features of this invention have been described in detailwith respect to various embodiments thereof it will, or course, beapparent that other modifications can be made within the spirit andscope of the invention, and it is not intended to limit the invention tothe exact details set forth above, except insofar as they are defined inthe following claims.

What is claimed is:

l. in a method of treating an oleaginous and proteinic vegetablesubstance including the steps of submitting said vegetable substance tomechanical pressure and friction forces in the presence of water, at atemperature higher than normal ambient temperature, and separating theoily constituents of said vegetable substance from the proteinicconstituents thereof, the improvement which comprises adding atannin-containing substance to said vegetable substance prior to saidstep of submitting said vegetable substance to said pressure andfriction forces, and adjusting the amount of water such that itcorresponds to a moisture content of about 10 to 15 percent of saidvegetable substance prior to separating said oily constituents from saidproteinic constituents, and separating said oily constituents from saidproteinic constituents.

2. The method of claim I, wherein said tannin-containing substance is atanning extract in the form of a solid powderous substance or in theform of a concentrated solution.

3. The method of claim 1, wherein said tannin-containing substance is atanning extract, the amount of said tanning extract added to saidvegetable substance being about 3 to 8 percent of the latter.

4. A product consisting at least in part of the proteinic constituentsof an oleaginous and proteinic vegetable substance, when said product isobtained by the method of claim 1.

5. A product consisting at least in part of the oily constituents of anoleaginous and proteinic vegetable substance, when said product isobtained by the method of claim I,

6. The method of claim 1, wherein said vegetable substance isconstituted by a substance selected from the group consisting of peanut,sunflower, colza, cotton, soya and, linseed, and wherein about 3 to 20percent of tanning extract are added to said vegetable substance,related to the weight of the latter.

2. The method of claim 1, wherein said tannin-containing substance is atanning extract in the form of a solid powderous substance or in theform of a concentrated solution.
 3. The method of claim 1, wherein saidtannin-containing substance is a tanning extract, the amount of saidtanning extract added to said vegetable substance being about 3 to 8percent of the latter.
 4. A product consisting at least in part of theproteinic constituents of an oleaginous and proteinic vegetablesubstance, when said product is obtained by the method of claim
 1. 5. Aproduct consisting at least in part of the oily constituents of anoleaginous and proteinic vegetable substance, when said product isobtained by the method of claim
 1. 6. The method of claim 1, whereinsaid vegetable substance is constituted by a substance selected from thegroup consisting of peanut, sunflower, colza, cotton, soya and, linseed,and wherein about 3 to 20 percent of tanning extract are added to saidvegetable substance, related to the weight of the latter.